Aguilera told TMZ last week that Lovato was "her girl" and "great things" were coming, and Lovato was quick to return the sentiment during the recent Dallas stop of her Tell Me You Love Me tour. "“Now Christina’s my girl and big things are coming,” she said onstage, according to People, repeatedly Aguilera nearly verbatim.

Their comments follow a series of clues the singers have been sharing in recent weeks. While at an intimate performance — also in Dallas — in February, Lovato revealed that she recently teamed with one of her "biggest idols" for a song. "I can’t give away who it is yet, but you’ll find out soon. I can’t wait for the world to hear it," she said at the time.

Afterward, fans speculated that she was referring to Aguilera, who she named as one of the leading influences for Tell Me You Love Me. "[Aguilera] was one of my idols growing up. She still is," Lovato explained to People in September. “I think it was her breakout album that really transformed her into the icon that she is today. So that inspired me … she really inspired this album. I was even inspired by the black and white artwork!”

Aguilera, meanwhile, promised fans in January that her next LP was on the way. "It's coming, bitches," she wrote of the project, which will mark her first album in over five years.

So if there is an Xtina-Lovato duet brewing — which at this point, seems all but confirmed — expect it to arrive with Aguilera's new music.